Vertical Dispersion - Weighing Primers

[Evan]

I bet the GemPro 250 would sort primers just fine.
My GemPro has always been very accurate.

I sold my AND FX-120i because is was just an oversized scale that didnt offer any advantage over what my GemPro 250 had already been doing for me.

I've been looking at picking up a FX-120i, but keep telling myself it won't make a difference on the target. In the last year I have with much greater consistency dropped below 0.5 inches at 300 yards and am starting to think that I may see some advantage to going down the rabbit hole on some of these more OCD tasks: weight sort primers, load charges to 0.02 instead of 0.1, sort bullets, sort brass by volume.

How quick is your GemPro 250? I'm thinking that I'd continue to throw charges on my Chargemaster Lite and transfer it onto another scale, which it seems like the GemPro could handle well. Would it handle really small weights, like a primer being transferred on and off, reliably?

 

[Rocketvapor]

How fine do you plan on sorting primers?
I get 3.65 grains for an average weight of CCI450's.
CCI250's are about 5 grains.
You probably don't have to use a powder trickler to weight primers
From the OP's results and my abbreviated test of 100 CCI450's,
outliers were at least couple percent from the mean.
Accepting +/-1% would exclude anything you could call light or heavy.
It doesn't take a $400 scale to sort primers to +/- 1%.

Even +/- 0.1 grain would catch the really light or heavy Small or Large Rifle Primers.
If you don't think your scale will weight all the way down to 3 or 4 grains, add a tare weight.

If you want to further sort them into 5 or 6 weight groups then Yes, a better scale is needed

 

[Ledd Slinger]

I've been looking at picking up a FX-120i, but keep telling myself it won't make a difference on the target. In the last year I have with much greater consistency dropped below 0.5 inches at 300 yards and am starting to think that I may see some advantage to going down the rabbit hole on some of these more OCD tasks: weight sort primers, load charges to 0.02 instead of 0.1, sort bullets, sort brass by volume.

How quick is your GemPro 250? I'm thinking that I'd continue to throw charges on my Chargemaster Lite and transfer it onto another scale, which it seems like the GemPro could handle well. Would it handle really small weights, like a primer being transferred on and off, reliably?

The GemPro does have a slower delayed response time than the FX-120i when trickling individual kernels into the pan. So I guess that's one disadvantage.

I do my load development with a scale that measures in .02gr. But after ladder testing, I throw my powder on a Chargemaster because I always try to find a charge weight with a good wide accuracy/POI node. The Chargemaster has always been plenty accurate enough to keep weights within the middle of my node window.

But I think "ignition" is a whole different beast than powder charge weights. And there have been times where I wondered why a bullet flew off target a time or two, but never became a consistent flyer. I can usually call errant shots quite well due to poor shooting form on my part and the type of flyers in question always felt like perfect shots. Definitely could have been out of spec primer changing the ignition rate of the powder charge enough that it threw it out of my node.

I recall last year when I bought a bunch of 6mm Creedmoor brass from a member here. 200 of the cases wer primed with standard Fed 205. I tried using them for initial load development. The primers must have been sitting in a humid environment for a long time because everyone of them had a split second hang fire. I had already loaded 40 rounds to test so I just made sure I held steady during the hang fires and finished the range session with them. Nothing shot great. Reloaded the cases with the same standard Fed 205s from my own inventory and went back to the range with the same loads. Night and day difference on the groups.

 

[dmoran]

Personally do a box of 1000 at a time, which takes me around 3-hrs. I open all 10 sleeves and put all the primers in a dish, then weigh them on a MX123 100th scale, qualifying them into small plastic cups, and cue out any extremes. After which, from the lightest batches to the heaviest, I put them back into the sleeves and mark the weight range on the sleeve (see image below), and in sequence use them in an order.

 

[mikeeg02]

Personally do a box of 1000 at a time, which takes me around 3-hrs. I open all 10 sleeves and put all the primers in a dish, then weigh them on a MX123 100th scale, qualifying them into small plastic cups, and cue out any extremes. After which, from the lightest batches to the heaviest, I put them back into the sleeves and mark the weight range on the sleeve (see image below), subsequently use them in the same order.

View attachment 1162600

I am lazy, and have it in my head not to touch the primers any more than need be. Plus, I have a TON of old berger 6mm boxes, which make for convenient primer storage, with a piece of "wicking" paper in there. I really dont enjoy sorting primers, probably worse than ANY single other step, but I have seen the benefits, and so have my aggregates.

 

[Rocketvapor]

You guys getting around 3.65 for an average with the 450's?
The boxes look like a better idea than trying to put them back in the trays.

 

[granite1]

When I read threads like this I get thinking I am skipping a step but then I remember this. I’m not knocking your efforts but this load in my rifle does this all time. Admittedly it’s not at 1,000 but it’s pretty flat.

 

[mikeeg02]

You guys getting around 3.65 for an average with the 450's?
The boxes look like a better idea than trying to put them back in the trays.

I'll have to look tonight. If I had to bet, those in my picture are probably 205m's. But the only other thing they could be is 450s lol

 

[Jdne5b]

View attachment 1162608 When I read threads like this I get thinking I am skipping a step but then I remember this. I’m not knocking your efforts but this load in my rifle does this all time. Admittedly it’s not at 1,000 but it’s pretty flat.

maybe weighing primers would reduce horizontal dispersion for you?

 

[dmoran]

@Rocketvapor
With a good Lot of 450's, typically they will range like from say: 3.66 - 3.76 (not including extremes).
The worse Lot of 450's I ever had, ranged from 3.58 - 3.86 (7.3%) that delivered pesky "fly'ers".... until I qualified them.

PS... to put them back into the sleeves, I simply poor each batch on a primer tray, then spout them down the rows of the sleeves.
Easy peasy... and they don't take up any more room.

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[quest450]

I switch my FX120 to grams for better resolution and sort primers by .001 gram......yeah I have issues, I know

 

[dmoran]

When I read threads like this I get thinking I am skipping a step but then I remember this. I’m not knocking your efforts but this load in my rifle does this all time. Admittedly it’s not at 1,000 but it’s pretty flat.

IME - fliers can go in any direction, and are not exclusive to vertical dispersion alone (as the OP entitled the thread).

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[JFrank]

View attachment 1162616 I switch my FX120 to grams for better resolution and sort primers by .001 gram......yeah I have issues, I know

So now that you have these sorted are you tuning around each set of different weight?

 

[quest450]

So now that you have these sorted are you tuning around each set of different weight?

hell no
but it helps my mental game and removes another variable I can control

 

[JFrank]

hell no
but it helps my mental game and removes another variable I can control

Thank Goodness

 

[quest450]

Thank Goodness

I'm nutz but I'm not crazy yet

 

[granite1]

maybe weighing primers would reduce horizontal dispersion for you?

Yeah I think being 20 years younger might be the answer.

 

[quest450]

And to take it step further here’s pretty good primer seater and a nice tool to measure primer pocket depth and primer seating depth.....yes I’m a control freak

 

[Ned Ludd]

I bet the GemPro 250 would sort primers just fine.
My GemPro has always been very accurate.

I sold my AND FX-120i because is was just an oversized scale that didnt offer any advantage over what my GemPro 250 had already been doing for me.

The GemPro250 has a readability of 0.001g. Note - that is readability, not precision, which is probably more like in the +/- 0.002g range (or worse). You're talking about using such a balance to sort primers by weight where the total weight variance for 100 primers might easily be less than 0.010g. A balance with 0.0001g readability would be a much better choice.

 

[MikeMcCasland]

It's kind of funny, this is the 4th or 5th thread I've seen on weighing primers, but the first in which we've got a decent number of people admitting to doing it, and detailing the methods. Makes me think there's probably 10-15 lurkers for every poster doing this kind of thing too.